The Bark Structure of a Tree

The outer protective covering tree trunks is the bark. The bark is a useful characteristic for tree identification because the form and structure differs greatly from tree to tree.

The bark has two layers:
Outer Bark- It is made up of dead cells which is usually thick.
Inner Bark- It is also called as the phloem which is made up of a thin layer of living cells. The cells have thin walls which allows water and nutrients to pass in the tree.